Polyethylene Glycol (PEG-400): As Efficient Reaction Medium for the Synthesis of 1,5-Dihydropyrano[2,3-c]chromene Derivatives

In this research, a simple and effective method for the synthesis of 1,5-dihydropyrano[2,3-c]chromene multi-substituted derivatives has been introduced, using the three-component reaction of aromatic aldehydes, malononitrile and 3-hydroxycoumarin at room temperature and in the presence of polyethylene glycol (PEG-400) as solvent and reaction catalyst. Easy method, short reaction time, high atom economy, high yields, environmental acceptability and the easy of separating of polyethylene glycol are included as the most important advantages of this method. Moreover, the produced products were obtained through simple filtering and no need to column and technique chromatography with high purity. Moreover, the produced products were obtained through simple filtering and no need to column and technique chromatography with high purity.